Method for Validating Ambiguous W3C Schema Grammars

摘要

A method for generating XML (Extensible Markup Language) parsers, including: parsing an input document with a generated parser where the generated parser is generated by a three-stage compilation of an XML Schema, where in a first stage the XML Schema is read and modeled in terms of abstract schema components, where in a second stage the XML Schema is augmented with a set of calculated schema components and properties, and where in a third stage the XML Schema is traversed to generate validation code; the validation code is generated by: calculating prohibited occurrence ranges; generating code to: evaluate each of the plurality of particles in an inner loop conditioned on an effective upper bound; then, once the inner loop terminates, check forbidden occurrence ranges for an inner particle, and calculate a range of possible repetitions of an outer particle; and once an outer loop terminates, check a range of total possible repetitions of the outer particle against its actual occurrence limits.